Re: Proposal for CSN based snapshots - Mailing list pgsql-hackers

From Heikki Linnakangas
Subject Re: Proposal for CSN based snapshots
Date
Msg-id f4ffe7d1-60db-7fda-949c-6863e370fa8b@iki.fi
Whole thread Raw
In response to Re: Proposal for CSN based snapshots  (Alexander Korotkov <a.korotkov@postgrespro.ru>)
List pgsql-hackers
On 08/10/2016 07:54 PM, Alexander Korotkov wrote:
> Do I understand right that now async commit right as follows?
> 1) Async transaction confirms commit before flushing WAL.

Yes.

> 2) Other transactions sees effect of async transaction only when its WAL
> flushed.

No. Other transactions also see the effects of the async transaction 
before it's flushed.

> 3) In the session which just committed async transaction, effect of this
> transaction is visible immediately (before WAL flushed). Is it true?

Yes. (The same session is not a special case, per previous point. All 
sessions see the async transaction as committed, even before it's flushed.)

- Heikki




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